Impelled powdered ink printing device and process using intaglio means



Oct. 18, 1966 G. T. BROWN. JR 3,279,367

IMPELLED POWDERED INK PRINTING DEVICE AND PROCESS USING INTAGLIO MEANS 5 Sheets-Sheet 1 Filed June 25, 1964 INVENTOR GEORGE T. BROWN, JR. BY fiif HIS ATTORNEYS FIG.2

Oct. 18, 1966 T BROWN, JR 3 279,367

G. 6 IMPELLED POWDERED INK PRINTING DEVICE AND PROCESS USING INTAGLIO MEANS Filed June 25, 1964 5 Sheets-Sheet 2 ITI g m m 2 m OOOOOOO OOOOOOO INVENTOR GEORGE T. BROWN, JR.

W3 ATTORNEYS Oct. 18, 1966 G. T. BROWN. JR 3,279,367

IMPELLED POWDERED INK PRINTING DEVICE AND PROCESS USING INTAGLIO MEANS Filed June 25, 1964 5 Sheets-Sheet 5 32 INVE NTOR GEORGE T BROWN JR His ATTORNEYS United States Patent 3,279,367 INHELLED POWDERED INK PRINTING DEVICE AND PROCESS USING INTAGLIO MEANS George T. Brown, Jr., Dayton, Ohio, assignor to The National Cash Register Company, Dayton, Ohio, a

corporation of Maryland Filed June 25, 1964, Ser. No. 377,866 16 Claims. (Cl. 101-450) The present invention relates to printing devices and, more specifically, to an impelled flowable ink high-speed printing device.

Many modern high-speed printers are dependent upon mechanical impact to transfer the characters to be printed from an embossed type slug or type wheel to the record material through a transfer medium such as an inked ribbon. Generally, the mechanical impact necessary with printers of this type is produced by mechanically, pneumatically, or electromagnetically operated hammers. The mechanical linkages required to operate the hammers at the high-speed requirements of today are subjected to considerable inertial problems and related mechanical stresses; therefore, the problem of maintaining these printers in operating condition is a significant factor. Moreover, the attendant high noise and vibration levels of these printers at high speeds is also quite objectionable.

Thermal and electrostatic type printers which require no mechanical motion to perform the printing operation have been developed to eliminate most of the maintenance problems which are present with impact type printers. However, printers of this type require special papers or record materials which are sensitive to heat or an electrical charge or field. Although papers of this type are commercially available, they are much more expensive than ordinary papers of record quality.

As the use of high-speed electronic data-processing equipment is becoming increasingly popular, the require me-nt of a high-speed device which will provide for printing upon any record material without mechanical impact motions to perform the printing operation is apparent.

It is, therefore, an object of this invention to provide an improved high-speed printing device.

It is an additional object of this invention to provide an improved high-speed printing device which performs the printing operation upon any record material without mechanical impact motion.

In accordance with this invention, a high-speed printing device which performs the printing operation upon any record material without mechanical impact motion is provided wherein a flowable marking material which is carried by a plurality of depressions in a marking material carrier is impelled from the carrying depressions by an impelling force positioned in operative relationship therewith and deposited in the form of printed character outlines upon a record material which is positioned between the marking material carrier and the source of impelling force.

For a better understanding of the present invention, together with additional objects, advantages, and features thereof, reference is made to the following description and accompanying drawings, in which:

FIGURE 1 shows a marking material carrier in the form of a drum,

FIGURE 2 schematically shows a system which utilizes a drum type marking material carrier,

FIGURE 3 shows a source of magnetomotive impelling force which may selectively produce a shaped magnetomotive force pattern,

FIGURE 4 illustrates an acceptable marking material carrier having the marking-material-carrying depressions arranged in columns and rows,

FIGURE 5 is a view, partially in section, of a record material positioned between the marking material carrier and the source of magnetomotive impelling force,

FIGURE 6 illustrates the type characters which may be printed through the use of a source of magnetomotive impelling force as shown in FIGURE 3,

FIGURE 7 is an alternate marking material carrier in the form of a drum, wherein the carrying depressions are the characters to be printed which have been engraved into the surface thereof, and

FIGURE 8 schematically shows a system which utilizes a belt type of marking material carrier.

With the novel printing device of this invention, the marking material is carried in carrying depressions upon the surface of a marking material carrier and is transferred to a record material by being impelled from the carrying depressions by the action of an impelling force. There is a wide selection of impelling forces which may be used in this regard. For example, magnetic and electrostatic attraction forces have been found to be quite satisfactory. As the marking material is impelled, it must be fiowable, and, should either magnetic or electrostatic forces be employed, it must react to the influence of these forces.

In a practical application of this invention, magnetic attraction forces were employed, and the marking material was a finely-divided magnetic powder consisting of:

These materials were ball-milled together several hours, sifted, and blended. The plastic resin components polymerized, upon being heated, to an insoluble polymer. Therefore, this marking may be permanently set by heat, as will be brought out later.

The novel features of this invention will be described on the basis of a magnetomotive impelling force acting upon the marking material formulation herein-above set forth. It is to be specifically understood that other impelli-ng forces may be employed and that liquid, paste, or other flowable marking materials having the required characteristics may be used without departing from the spirit of the invention.

The characters to be printed may be outlined by selectively shaping the impelling force in the form of the character to be printed, or the carrying depressions in the surface of the marking material carrier may be shaped in the form of the characters to be printed, whereby each character may be transferred by selective application of the impelling force. With the former, the characters are outlined as a series of shaped spots, as shown in FIGURE 6; with the latter, the characters are outlined as with conventional printing methods. The shaped impelling force technique is probably more flexible and permits faster character selection than the alternate technique, and will be described first.

For purposes of illustrating the features of this invention, the printing of a single character by the shaped impelling force technique will be described. Referring to FIGURE 4, there is illustrated a marking material carrier 10, having thirty-five ma-rking-material-carrying depressions upon its surface, arranged in the form of a matrix of five columns, A, B, C, D, and E, and seven rows, 1, 2, 3, 4, 5, 6, and 7. It is to be understood that this invention is not to be limited to this specific arrangement of the marking-material-carrying depressions, as alternate arrangements or patterns maybe used. However, it has been found that all of the letters of the alphabet and all of the numerical digits may be conveniently printed with this arrangement of mar-king-material-carrying depressions.

The source of shapable impelling force may be magnetomotive and may consist of a plurality of elongated magnetic pole pieces, one for each marking-material-carrying depression, arranged in such a manner that each pole piece and the corresponding marking-material-carrying depression are positioned substantially in register with each other when the marking material carrier and the source of magnetomotive impelling force are placed in operative position. With the marking-material-carrying depressions arranged as shown in FIGURE 4, the pole pieces of the magnetomotive impelling force source are also arranged in columns and rows, corresponding to those of the record-material-carrying depressions in the marking material carrier 10. In FIGURE 3 is illustrated a suitable magnetomotive impelling force source for use with this invention. To avoid drawing confusion, only those elongated pole pieces which correspond to Row 7 and Column E of the marking material carrier 10 of FIG- URE 4 have been illustrated. It is to be understood, however, that a pole piece is required for each of the marking-material-carrying depressions contained in the marking material carrier 10 and must be arranged in a manner to substantially correspond thereto. For purposes of this description, the pole pieces of FIGURE 3 which have been illustrated are referenced as P7A, P7B, P7C, P7'D, P7 15, P6151, PSE, =P4E, P3E, P2E, and P1E. Each of the elongated magnetic pole pieces has wound thereon an individual electrical coil referenced in FIGURE 3 as 07A, C713, C7C, C7D, C7E, 06E, E C4E, CSE, CZE, and and C1 E, respectively. Energization by an electrical pulse of any one of these coils produces a magnetometive force in the corresponding magnetic pole piece in a manner which is well known in the art. In a practical application of this novel printing device, the elongated pole pieces were made up of .010" diameter pure annealed soft iron wire, and the corresponding coils consisted of 200 turns of copper wire. Ferrite materials may also he used for these pole pieces. To produce the required magnetomotive force to impel the flowable mark i-ng material from the corresponding marking-materiaL carrying depressions, each of these coil-s was energized by two amperes of direct current. To support this source of magnetornotive impelling force, the entire unit may be enclosed within a plastic resin, or, alternatively, that portion of the several pole pieces which does not include the wind ings may be potted in a resin material to maintain them in their proper respective positions. With the latter alternative, the coils may be replaced in the event of the destruction of any one of them.

To place the magnet-omotive force impelling force source in operative relationship with the marking material carrier 10 (FIGURE 4), the ends of the several pole pieces of the magnetomotive impelling force source are positioned substantially in register with and displaced from the corresponding marking-material-carrying depressions in the marking material carrier, and the record material is placed therebetween. This relationship is schematical'ly illustrated in FIGURE 5, where the pole pieces P7E, PGE, PSE, P4E, P3-E, PZE, and P115, are located in register with the cor-responding marking-material-carrying depressions in the marking material carrier 10, and the record material 11 is disposed therebetween. The energization of any or all of the coils associated with the corresponding pole pieces creates therein a magnetomotive force which impels the fiowable marking material from the corresponding marking-material-carrying depression in the carrier 10 in a direction toward the corred spending pole piece. As the record material 11 is disposed therebetween, the impelled marking material is deposited thereon. From this description, it is readily apparent that this novel unit effects printing by outlining the char acters to be printed as a series of shaped spots on the record material, as illustrated in FIGURE 6.

Since each of the electrical coils of the pole pieces of the source of magnetomotive impelling force may be individually and selectively energized, the impelling force may be shaped by energizing selected ones of these coils to form the outline of the character to be printed. For example, to print the letter N, illustrated in FIGURE 6, the electrical coils associated with the magnetic pole pieces of the magnetomotive impelling force source corresponding to the marking-material-carrying depressions 1A, 2A, 3A, 4A, 5A, 6A, 7A, 4B, 3C, 2D, 1'E, 2B, 3B, 4E, 5E, 6E and 7B are energized with an electrical pulse. The magnetomotive force produced in each of the corresponding pole pieces may be thought of as shaped like the letter N, and the marking material contained within the corresponding marking-material-carrying depressions is impelled therefrom and deposited as a series of dots in the outline of the letter N upon the marking material disposed between the marking material carrier and the source of magnet-omotive impelling force. In a similar manner, other selected combinations of electrical coils may be energized to produce in the corresponding magnetic pole pieces a magnet-omotive impelling force which is shaped in the form of the outline of the character to be printed. As the source of the electrical pulses which are employed to energize the coils of the pole pieces of the magnetomotive impelling force source may be conventional in design and may be any one of the short-durationpulse circuits well known in the art, such as a one-shot multivibrator, for example, it has not been shown herein, in the interest of reducing drawing complexity. In a practical application of this invention, however, it was found that a pulse duration of five microseconds was sufficiently long to perform the printing operation.

The size of the marking-material-carrying depressions is, of course, dictated, to a large extent, by the size of the character to be printed. It has been found, however, that the legibility of the printed characters improves as the outline of the dots approaches the outline of a continuouslywritten character. Round pole pieces may be used to transfer the marking material from square or rectangular cavity molds for more continuous character outlines. This ideal outline is more closely approached as the spacing between adjacent elements, both columns and rows, is minimized. In view of this, the most satisfactory charac tors are printed by marking material carriers which have marking-material-carrying depressions of a width dimension substantially equal to the length dimension and as closely spaced as is practical without physical contact therebetwee-n. In the interest of drawing clarity, the spacing between the marking-material-carrying depressions has been exaggerated in the pertinent figures. Furthermore, the marking-matedal-carrying depressions have been indicated in the drawings to be circular in form. It is to be specifically understood that other geometric shapes, such as rectangles, hexagons, or, possibly, triangles, may be used without departing from the spirit of the invention. In fact, rectangular marking-materialcarrying depressions are probably the most desirable; however, since the pole pieces of the magnetomotive impelling force source which was used with the practical application consisted of circular iron wires, the corresponding marking -material-carrying depressions were formed with a circular configuration to conform thereto, thereby providing the most efiicient transfer of the marking material from the marking material carrier to the record material. The marking-material-carrying depressions in the marking material carrier 10 were approx-- imately .017 inch in diameter and .010 inch deep.

After the marking material has been transferred to the record material by the shaped magnetomotive force, it may be permanently fixed by the application of heat in a manner to be later described in connection with a more practical printing unit employing the features just described.

While the printing of only a single character has been described to illustrate the principles of this invention, the features are readily adaptable to line printing or page printing.

To provide line printing, the marking material carrier device may be extended to accommodate additional columns of marking-material-carrying depressions. With additional columns of marking-material-carrying depressions, additional characters may be printed in the same line without additional movement of the record material of the printing device. It follows, therefore, that the marking material carrier may be extended to accommodate enough additional columns of marking-materialcarrying depressions to print a line of characters with each position of the record material. The line of characters may be printed simultaneously or sequentially across the record material as determined by considerations with which this specification is not concerned.

To provide page printing, the marking material carrier may also be extended to accommodate additional rows of marking-material-carrying depressions. With additional rows of marking-material-carrying depressions, additional lines of characters may be printed without additional movement of the record material or the printing device.

In each instance, it is necessary that the impelling force source be comparably enlarged to provide a pole piece for each marking-material-carrying depression. It is not necessary, however, that the enlarged impelling force source be of one-piece construction. In fact, to facilitate manufacture and maintenance, the larger impelling force source is better to be built up of smaller segments. It is only necessary that the impelling force source have a plurality of pole pieces and associated selectively energizable electrical coils wound thereupon and be positioned relative to the marking material carrier in such a manner that each of the pole pieces is in substantial register with and displaced from a corresponding markingmaterial-carrying depression upon the surface of the marking material carrier for impelling, upon the energization by an electrical pulse of selected ones of the electrical coils, the flowable marking material from those marking-material-carrying depressions corresponding to those pole pieces associated with the energized coils.

Because the marking material which is impelled from the marking-material-carrying depressions must be replaced to provide a continuous printing operation, continuous marking material carriers are important; that is, a carrier device which has many more marking-materialcarrying depressions than are necessary to print the desired characters whereby the depressions not adjacent the impelling force source are being replenished with marking material while the printing operation is taking place from another group of depressions.

In a practical printing device, it was found that a continuous marking material carrier may be conveniently in the form of a cylinder or rotatable drum 20, as shown in FIGURE 1, but is not specifically limited to this form, as alternative carrier configurations may be employed without departing from the spirit of the invention. The surface of the marking material carrier is provided with a plurality of marking-material-carrying depressions indicated generally at 21 (FIGURE 1) for carrying the marking material. While these depressions may be random, so that a single pole piece may cover a number of them, it has been found to be probably more satisfactory to arrange these depressions in such a manner as to form columns and rows should the drum carrier surface be thought of as a plane surface which has been wrapped around the circumference of the drum. That is, the marking-material-carrying depressions would be essentially arranged in columns and rows similar to those illustrated in FIGURE 4, but of a greater number. The drum 20 is rotatable and may be of any desired length or may be of a specific length to accommodate a full-sized sheet of paper or of a size sufficiently Wide to accommodate characters, or any other desired printing width. As each character is printed to correspond to a matrix of marking-material-carrying depressions which, in this example, is five in width, to print 120 characters across a sheet of record material, 600 columns of depressions are required axially across the face of the drum. To provide spacing between the characters, added spaces may be left between every fifth column.

Referring now to FIGURE 2, an end view of an application of the drum 20 of FIGURE 1, a supply of flowable marking material 22 is located as indicated in a suitable supply hopper 23. As the drum is rotated counter-clockwise, the marking-material-carrying depressions are filled from the supply 22 in the hopper 23, and the excess is removed and leveled by a wiper seal 24, which may be a doctor blade of rubber, polyurethane, or other elastomeric material. As the drum continues to revolve counter-clockwise, the surface is thoroughly leveled and the surrounding matrix again cleaned by the action of another flexible w-iper 25, and any loose excess is removed by the associated vacuum exhaust port and hose 26. The record material 27, which may be in strip form, is passed over guide rollers 28 and 29, which direct it between the marking-material-carrying drum 20 and the source of magnetomotive impelling force 30, as indicated. This magnetomotive impelling force source may be that illustrated in FIGURE 3, and the seven pole pieces of each column, which determine the height of the character to be printed, are herein indicated in exaggerated form in the interest of drawing clarity. To locate the several print positions as the drum revolves, a commutator 31 (FIGURE 1) may be contacted by an electrical brush which produces an impulse at the end of each segment, herein indicated as axial lines, thereby indicating that the drum-type carrier is in a print position and that the mark ing-material-carrying depressions provided in the surface of the record material carrier drum 20 are in substantial register with the corresponding pole pieces of the magnetomotive impelling force source 30. At this time, therefore, a character may be printed by energizing the proper coils of the source 30 to produce a magnetomotive impelling force which is shaped as the character to be printed, in a manner previously explained in regard to FIGURES 3, 4, and 5. This commutator may also be located elsewhere, so long as it is associated with the drum. After the printing has been effected, the record material passes through a heating device 32, which, since it forms no part of this invention and may be any of the many conventional heating devices well known in the art, has herein been indicated in block form. This heat fixes the marking material upon the record material, and the printing operation is complete. It is apparent that, with a drum type or similar type of marking material carrier as herein indicated, a line-at-a-time printer may be provided. If a commutator pulse is provided for every axial line of depressions, then facsimile printing can also be accomplished, or, by various commutator pulse counts, one may pulse various sectors of even larger arrays of pole pieces (such as 50 x 70) to print out many different area sizes, such as headline types, etc., intermixed with smaller text, all utilizing the same matrix of pole pieces controlled by external switching logic.

As the logic circuitry which provides the energizing pulses for the magnetomotive impelling force source 30 forms no part of this invention, it has not been included herein, in the interest of reducing drawing complexity.

There is a wide latitude in the selection of materials which may be used for the marking material carriers, and the material in which the marking-material-carrying depressions are provided may be different from that of the core of the carrier. A very suitable drum-type marking material carrier of this type was found to be one having an aluminum core, about the circumference of which was secured a strip 40 of plastic material such as that marketed under the trademark Teflon by E. I. du Pont de Nemours and Company. The material of the marking material carrier, however, is not to be restricted thereto, as the marking material carrier material may be any of a wide variety which are substantially corrosion-free and which form a minimum of resistance to the impelling of the marking material therefrom.

An alternative arrangement for the marking-material carrying depressions is shown in FIGURE 7, where the characters to be printed are engraved into the surface of the marking material carrier and are, themselves, the marking material-carrying depressions. That is, the marking-material-carrying depressions are of the shape of the characters to be printed. All of the characters to be printed are included in a column about the circumference of the drum, and there may be as many of these columns as the number of lines to be printed thereby. As with the device previously described, with a IZO-character-perline printer, there would be120 engraved character columns about the periphery of the drum.

With marking-material-carrying depressions of this engraved character type, it is only necessary that the magnetomotive impelling force source have a single pole piece for each column, instead of the matrix of thirtyfive, as required with the printing technique previously described, and it should be of a cross-sectional area sufficient to cover the character size as determined by the size of the characters engraved into the surface of the marking material carrier drum. In a practical application of this invention, it was found that a /s-inch shaped spot of magnetic iron oxide powder ink composition could be impelled as an intact entity across an air gap of approximately 0.010 inch with perfect resolution by a five-microsecond pulse energizing the coil of a single ferrite composition pole piece.

As the logic required to energize the pole piece coil at the proper moment when the character to be printed is in register with it in the row in which it is to be printed is well known in the art and may be similar to that used with impact printers and type wheels of wellknown design, it forms no part of this invention and has not been included herein in the interest of reducing drawing complexity.

It has been determined that, although an extremely short-duration pulse will start and impel the marking material from the carrying depressions, the actual transfer from the carrying depressions onto the record material takes place over a longer period of time. This has proved to be a distinct advantage with a printing device as illustrated in FIGURE 2. With this arrangement, the record material and the drum-type marking material carrier can move synchronously or together during the period that the record material is in contact with the drum. Therefore, the physical transfer of the marking material to the record material may take place for a considerable time after the initial kick or impelling force has been removed, and without smudging or streaking the print.

An eight-inch-diameter drum, as an example, having line-printing matrices about its circumference on onefourth-inch centers, would need to rotate only one revolution in one second in order to print out one hundred lines per second.

With a printer employing this novel concept, printing may be effected upon any grade of paper, the quantity of marking material transferred is metered and the edges are sharply defined, thereby insuring uniform quality print, it is silent in operation and simple in construction and maintenance, it may be adaptable to a variety of print widths, it will accept torn or damaged record material without jamming, it is capable of dot-matrix or line-character printing, the printing element is synchronous with the record material, and the period of contact between the record material and the printing element is selectable by adjustment of the relative positions of the rollers 28 and 29, thereby permitting more thorough marking material setting.

An alternate continuous marking material carrier arrangement is shown in FIGURE 8, wherein the marking material carrier is in the form of a movable belt 41. This arrangement is very similar to that of FIGURE 2, and like parts have been given like characters of reference. The belt 41 may be endless, but not necessarily so, and is movable over pulleys 50 and 51. The marking-materialcarrying depressions are upon the surface of the belt 41 and may be of either type hereinbefore described. With this arrangement, the added feature of a magnetic or electrostatic device 52 may be employed to facilitate the replenishment of the marking material in the carrying depressions.

While a preferred embodiment of the present invention has been shown and described, it will be obvious to those skilled in the art that various modifications and substitutions may be made without departing from the spirit of the invention, which is to be limited only within the scope of the appended claims.

What is claimed is:

1. A printing device for printing on a record material without mechanical impact, comprising (a) a marking material carrier with a surface having a plurality of marking-material carrying depressions,

(b) flowable magnetically-influenced marking material disposed in each of said depressions,

(c) means to produce an impelling magnetic force capable of selectively impelling said flowable marking material from said depressions, the means to produce said impelling magnetic force being a plurality of magnetic pole pieces, each magnetic pole piece having an associated selectively energizable electrical coil wound thereon, and

((1) means to direct the record material between said marking material carrier and said impelling force means.

2. A device as in claim 1 wherein the markingmaterialcarrying depressions are circular in shape and are arranged into a matrix of columns and rows upon the surface of said marking material carrier.

3. A device as in claim 2 wherein each marking-material-carrying depression is in register with a magnetic pole piece.

4. A device as in claim 3 wherein the marking material carrier is an endless belt.

5. A device as in claim 3 wherein the marking material carrier is a rotatable drum.

6. A device as in claim 5 wherein the markingmaterial-carrying depressions extend axially across the face of said marking material carrier.

7. A device as in claim 6 wherein a commutator is employed to locate each print position of said marking material carrier.

8. A device as in claim 7 wherein (a) a heating means is positioned to receive the record material after printing, said heating means being constructed to set the marking material deposited upon said record material, and

(b) a hopper replenishes the marking-material-carrying depressions prior to each printing operation.

9. A printing device for printing on a record material without mechanical impact, comprising (a) a marking material carrier with a surface having a plurality of marking-material-carrying depressions, said depressions being pro-formed into image shapes which are to be printed,

(b) flowable magnetically-influenced marking material disposed in each of said depressions,

9 19 (c) means to produce an impelling magnetic force 16. A device as in claim 15 wherein capable of impelling said fiowable marking material (a) a heating means is positioned to receive the record from said depressions, the means to produce said immaterial after printing, said heating means being conpellin-g magnetic force being a plurality of magneti structed to set the marking material deposited upon pole pieces, each magnetic pole piece having an ensaid record material, and ergizable electrical coil wound thereon, and (b) a hopper replenishes the marking-material-carrying (d) means to direct the record material between said depressions prior to each printing operation.

marking material carrier and said impelling force R f means. e erences Cited by the Examiner t A deviced as in claim 9 wherein thehmarkinga-ma- UNITED STATES PATENTS ena -carrymg epressions are circu ar in s ape an are arranged into columns and rows upon the surface of said guderfer' marking material carrier to form the image shapes which are to be printed. 2,841,461 7/1958 Gleason. 11. A device as in claim 10 wherein each marking-ma- Stem terial-carrying depression is in register with a magnetic 2978968 4/1961 ggz pole piece.

12. A device as in claim 11 wherein the marking rnai terial carrier is an endless belt. 3068479 12/1962 13. A device as in claim 11 wherein the marking ma- 3081698 3/1963 5 9 3 a 1 terial carrier is a rotatable drum. 3120806 2/1964 8 1 fess a 14. A device as in claim 13 wherein the marking-ma- 12/1 64 i terial-carrying depressions extend axially across the face 1615 1 2/196 3 Wertz' of said marking material carrier. 4 1 9 4 15. A device as in claim 14 wherein a commutator is employed to locate each print position of said marking ROBERT PULFREY Prlma'y Examiner material carrier. E. S. BURR, Assistant Examiner. 

1. A PRINTING DEVICE FOR PRINTING ON A RECORD MATERIAL WITHOUT MECHANICAL IMPACT, COMPRISING (A) A MARKING MATERIAL CARRIER WITH A SURFACE HAVING A PLURALITY OF MARKING-MATERIAL-CARRYING DEPRESSIONS, (B) FLOWABLE MAGNETICALLY-INFLUENCED MARKING MATERIAL DISPOSED IN EACH OF SAID DEPRESSIONS, (C) MEANS TO PRODUCE IN IMPELLING MAGNETIC FORCE CAPABLE OF SELECTIVELY IMPELLING SAID FLOWABLE MARKING MATERIAL FROM SAID DEPRESSIONS, THE MEANS FOR PRODUCE SAID IMPELLING MAGNETIC FORCE BEING A PLURALITY OF MAGNETIC POLE PIECES, EACH MAGNETIC POLE PIECE HAVING AN ASSOCIATED SELECTIVELY ENERGIZED ELECTRICAL COIL WOUND THEREON, AND (D) MEANS TO DIRECT THE RECORD MATERIAL BETWEEN SAID MARKING MATERIAL CARRIER AND SAID IMPELLING FORCE MEANS. 